With the increased use of optical communication links and storage devices there is an increasing need to produce faster, lower cost and more power-efficient optical laser diode collimator assemblies. While initially light emitting diodes were utilized for optical links, they have never been practical for optical storage devices, while the use of laser diodes for communication links is increasing dramatically.
One of the requirements of laser diode collimator assemblies is the great precision with which they must be mounted in a package for optical collimation. As is well known, small misalignments can significantly optical degrade performances. This therefore, results in sometimes expensive and elaborate manufacturing costs, processes, and schemes, in order to ensure accurate alignment.
One such scheme may be found in U.S. Pat. No. 4,787,088 "Semiconductor Laser Beam Source Apparatus" issued Nov. 22, 1988 to Horikawa. This device provides a laser beam case which tries to protect the face of the laser from atmospheric exposure and contamination. However, this is somewhat unsatisfactory in that significant extra apparatus such as heaters and the like are needed in order to maintain proper ambient conditions.
U.S. Pat. No. 4,567,598 "Optoelectronic Semiconductor Devices in Hermetically Sealed Packages" issued Jan. 28, 1986 to Noguchi et al. discloses a hermetically sealed device. Unfortunately encompassed within this device is a significant number of components and it is therefore difficult to manufacture and optically tune the laser to the housing. U.S. Pat. No. 4,366,492 "Semiconductor Laser Device" issued Dec. 28, 1982 to Kitamura discloses a Semiconductor Laser and utilizes a metal cap or casing to house the laser. The purpose of the housing is to effectively suppress stray light emitted from the laser.
U.S. Pat. No. 4,003,074 "Hermetically Sealed Injection Semiconductor Laser Device" issued Jan. 11, 1977 to Yonezu et al. discloses another hermetically sealed laser device. However, this device is quite complex in structure with a significant number of components, thereby making it difficult to manufacture.
It is therefore an object and advantage of the present invention to produce a hermetically sealed laser package. Another object is to produce a laser package which has a minimal number of components. Yet another object and advantage is the production of a device which allows the laser package to be tuned so as to maximize the collimation of the light beam emanating from the package.
Accordingly, it is an object and an advantage of the present invention to produce a laser diode assembly comprising a laser diode for producing optical energy, a lens for collimating light produced by the laser diode means, and a housing having the diode disposable therein and having the lens optically adjustable with respect to the diode and being mountable within the housing.